Rotary compressor



Apr. 17, 1923. ]1,452, U 24% H. A. CAMPBELL 6 Sheets-Sheet 1 Filed Jan. 26 1921 6 She e t s-She e t 2 A TTOR NE Y Apr. 17, 1923.

* T,4l52,24 H. A. CAMPBELL ROTARY COMPRESSOR Filed Jan. 26 1921 6 Sheets-Sheet 15 A T TOR NE Y Apr.17,1923.. 11,452,024

-. H. A. CAMPBELL ROTARY COMPRESSOR A T TOR NE Y Apr. 17, 1923.

6 Sheets-Sheet 5 I VEN TOR HENRY 1)- C/9/7PE/EZL @AM- 8 jf -4uzi/ H. A. CAMPBELL I ROIAR COMPRESSOR Filed Jan. 26 1921 A T TOR NE Y Apr. 17, E923. 1,452,@24-

- H. A. CAMPBELL ROTARY co1vu=mssora Filed Jan. 26 1921 e Sheets-Sheet 6 A TZT'ORNE Y Patented Apr. 17, 1923.

HENRY A. CAMPBELL, OE 0AKL, CALIJE'OIA.

ROTARY COMPRESSOR.

Application filed January 1921.

To all whom it may concern Be it known that I, HENRY A. CAMPBELL, a citizen of the United States, residing at Oakland, in the county of Alameda and State of California, have invented new and useful Improvements in Rotary Compressors, of which the following is a specification.

This invention relates to a rotary compressor.

()ne of the objects of the present invention is to provide an improved and simplified air compressor of the rotary type, and especially to increase the general efficiency of the same, first, by decreasing friction and leakage to a,rninimum, and secondly by providing. ra mechanism in which reciprocal parts -iire practically eliminated.

Another object of the invention is to construct a compressor which includes a cylinder, a. 1i:0tor therein, and a pair of radially disposed vanes, and especially to provide a pair of vanes which are sectional in construction and automatically extensible and cont-ractable during rotation of the rotor.

Another object of the invention is to provide a vane of the character described which will automatically take up any wear that may take place, and which will reduce leakage between the vanes and the cylinder to a 2 minimum.

Another object of the invention is to pro vide a series of removable auxiliary cover plates whereby interior parts most subject to wear may be readily removed for inspect'on, repairs, etc.

Another object of the invention is to provide a rotor and cylinder construction which will permit a combined system of air and water cooling to be employed.

Further objects will hereinafter appear.

The invention consists of the parts and the construction, combination and arrangement of parts as hereinafter more fully descr'bed and claimed, having reference to the accompanying draw'ngs, which- Fig. 1 is an end view of the compressor.

Fig. 2 is a central vertical longitudinal section through the compressor.

Fig. 3 is a central cross section taken on line 33, Fig. 2.

Fig. 4 is an end view of the compressor showing one of the head members removed.

Fig. 5 is a perspective view of one of the vanes partly in section.

Serial No. 439,909.

Fig. 6 is a central cross section of Fig. 5.

Fig. 7 is a perspective view of one of the end members in the vane.

Fig. 8 is a perspective view of the base section of the vane, and showing the face section in dotted lines.

Referring to the drawings in detail, A indicates a cylinder in which is formed a central chamber 2. The cylinder illustrated in the present instance is water-jacketed as at I3 for cooling purposes, and it is otherwise provided with a pair of annular end flanges 4 for the purpose of receiving a pair of cylinder heads and the heads shown being also water-jacketed as at 7 to permit cooling of the same.

Formed integral with the head members 5 and 6 are bearing members 8; said bearing members being supported by spoke-like projections 9 forming a part of the respective heads. Journalled in the bearing members 8 is a main shaft 10, and keyed or otherwise secured thereon is a piston rotor 11. The rotor is supported with relation to the shaft by means of a central hub member 12 and a series of spokes 13; these spokes and hub being formed as an integral part of the rotor as shown. The rotor s otherwise cored out to lighten the structure as much as possible and to form a central air passage through which air may be circulated for cooling purposes as will hereinafter be described. Formed on opposite s des of the rotor and radially positioned therein, is a pair of slots 14:, and slidably mounted in each slot is a vane generally indicated at 1.3. There are two vanes employed in the present instance, one being disposed in each slot, and these vanes are connected by a central rod which extends through the hub 12 and the shaft 10. The detail construction of the vanes employed is an important feature of the present invention and as such will be described in detail.

Referring to Figs. 5 and 6. it will be seen that each vane consists of a base section 16, a face section a pair of end sections 18, and a contact shoe 19. The base sections of the respective vanes are connected by the rod 15, and they are adjustable with relation to each other by threading the rod into "the respective shoes and securing the rod when adjusted by means of lock nuts 15*. The base section of each shoe is otherwise recessed along each side as at 20 to receive overlapping side sections 21 of the face section 17. In other words the face section 17 is channeled to permit it to telescope over a. central longitudinal extending sect-ion 22 formed on the base member; th1s telescoping action of the face section of each vane being necessary as the rotor proper is eccentrically positioned with relation to the cylinder bore and as such requires extension and contraction of the respective vanes once during each rotation of the rotor. Such extension and contraction of the vanes is permitted in this instance by forming the telescoping connection between the vane sections and by interposing a spring 23 between the same which normally forces the face sections outwardly. The face section is otherwise provided with a pair of downwardly projecting end sections 24 and a foot 25. These end sections 24 are provided for the reception of the end plates 18; said end plates being provided with side extensions 26 which partly embrace the sections 24:. The foot extensions 25 form a support for the end sections 18, which limits the downward movement of the same, and they also form a support for a spring 27 interposed between the sections 24 and the end sections 18; said spring serving the normal function of maintaining the end sections in contact with the cylinder heads. The shoe 19 is supported both by the end sections 18 and the face section 17. It is semi-circular in cross section and its outer face is machined to conform to the inner contour of the cylinder. The shoe contacts with the inner face of the cylinder and is held in frictional engagement therewith, first by the outward pressure of the spring 23, and secondly by centrifugal pressure created during rotation of the rotor, that is the face section 17 supports both the end sections 18 and the shoe 19, and as the face section in turn is freely movable with relation to the base section 16, it is obvious that both the face section, the end sections 18 and the shoe 19 are equally affected by centrifugal force and the action of the spring 23. Leakage between the outer end of the vane and the cylinder should. therefore, be reduced to a minimum. and leakage between the shoe 19 and the sections supporting the same should also be small, if any, as the shoe is semi-circular in cross section and as such affords a large bearing surface and contact. Leakage between the ends of the vanes and the cylinder heads is taken care of by the end sections 18. and any wear that takes place between said members is automatically taken up by the action of the springs 27.

The several parts, forming each vane, are readily assembled and as such forms a pair of units which automatically takes up wear wherever necessary. The recessing and overlapping of the respective parts with relation to each other takes care of leakage between the several parts.

To prevent leakage between the ends of bein illustrated at 28 and the other pair at 30. he ends of the respective pairs contact with the sliding vanes and as they are eccen trically positioned, it is obvious that they will sweep over a comparatively large area as far as the cylinder heads are concerned and as such will prevent cutting or grooving of the heads.

To prevent leakage between the rotor and the cylinder, a sealing shoe such as indicated at 31 is provided. This shoe is placedin a pocket 32 formed in the cylinder, and it is pivotally mounted therein as at 33. A spring 34 is interposed between the outer face of the shoe and the inner face of the pocket; this spring exerting sufficient pressure on the shoe to prevent leakage between the shoe and the rotor. Leakage around the ends of the shoe is prevented by grinding the faces and closely fitting the heads engaging the same, and leakage around the pivot point of the shoe is similarly prevented by grinding the adjoining parts and closely fitting the same;

In actual practice it is obvious that the cylinder A is provided with an inlet port 40 and a corresponding discharge port 41. These ports are disposed on opposite sides of the sealing shoe 31 and will therefore permit a maximum charge of air to be admitted and compressed twice during each revolution.

Referring to Fig. 3, the direction of rotation of the rotor is such as is indicatel by arrow a-. The vane indicated at B, which has just passed the inlet port 40, will during the rotation of the rotor produce a vacuum at the rear thereof and will thus induce a flow of air through the port 40. This charge of air admitted by suction will be pocketed or entrained within the cylinder the moment the second vane B sweeps past the intake port 40. The charge first admitted will now be gradually compressed ani will discharge through the port 41. One of the vanes or that opposite the intake port 40, see Fig. 3, is just in a position where it is expelling a compressed charge as the air entrained in advance of the same has no other path of escape, except through the port 41. This port may be connected through a pipe l U l) with a storage tank, or otherwise, and any pressure desired may be built up therein.

By again referring to Fig. 3, it W1ll be seen that a slight chamber is formed behind the vane 31 as at 50. This chamber communicates with the discharge port 41 through an auxiliary port 51. Apart of each compressed charge is thus admitted to the rear side of the sealing shoe and is thereby permitted toexert its pressure on the shoe; the pressure exerted increasing as the pressure on the discharging charge increases. In other words means is provided for increasing the pressure on the shoe as the charge compressed increases in pressure. The small amount of air admitted to the chamber 50 automatically escapes or returns to the port the moment the vane passes, and it may therefore be stated that a small volume of air is alternately compressed and expanded twice during each revolution of the rotor as the cycle of operation is the same in regard to both vanes.

Another feature of the invention is the provision of one or more auxiliary cover plates as indicated at 60 and 61. see Fig. 1. These cover plates may be readily removed as they are merely screwed or bolted to one of the cylinder heads. The plate forms a closure for the pocket in which the sealing shoe is mounted. The sealing shoe may therefore be removed from time to time for inspection, repairs or otherwise. The contact shoes 19 may similarly be removed when the plug or cover member is released. The sealing shoe 31, together with the contact shoes 19, are. practically speaking, the only parts that are subjected to wear, and as these may be quickly and readily removed whenever desired without taking the machine as a whole apart. it is obvious that the upkeep and care of the compressor can easily be attended to.

Several important features are obtained by constructing a compressor in the manner here described and shown: first, maximum eiiiciency in regard to cooling of the same may be obtained as the exterior of the cylinder and the heads employed may be cooled by water circulation, and interior cooling may be resorted to by air circulation as the heads are spoked as at 9 to support the bearings, and the piston proper is cored and spoked to carry the hub 12. This coring and spoking of the parts forms a central passage through which air will automatically circulate during the operation of the compressor, thus permitting efficient cooling of all parts.

Another important feature is the provision of a pair of vanes which are automatically extensible and contractable during the rotation of the rotor, and which will automatically take up wear in every direction.

Another important feature is the provision of the sealing shoe, whereby leakage between the rotor and the cylinder is prevented; and a further important feature is the provision of removable auxiliary cover plates which permit inspection and renewal of the parts which are most subject to wear.

The machine illustrated in the drawings has heretofore been referred to as a compressor. will be equally efficient as a vacuum pump, and while certain features of the present invention are more or less specifically de scribed and illustrated, it should be obvious that various changes may be resorted to within the scope of the appended claims. Similarly that the materials and finish of the several parts employed may be such as the experience and judgment of the manufacturer may dictate or varying uses may demand.

Having thus described my invention, what I claim and desire to secure by Letters Patent is-- 1. In a compressor of the character described a vane comprising a base section, a face section having end portions lying parallel with the ends of the base section, the ends of the face section being recessed, and an auxiliary extensible end section supported in the recess of each end of the face section.

2. In a compressor of the character described a vane comprising a base section, a face section having end portions lying parallel with the ends of the base section, the ends of the face section being recessed, and an auxiliary extensible end section supported in the recess of each end of the face section, the face section having a longitudinal groove therein and the said auxiliary extensible end section having each a groove therein adapted to align with the longitudinal groove of the face section, and a rocking contact shoe mounted in said aligning grooves.

3. in a compressor, a cylinder, a rotor eccentrically ositioned therein, opposed radial slots formed in the rotor, a vane in each slot, a member connecting the same, a telescoping extensible section on the outer end of each vane telescoping extensible and sections on the ends of each vane, and a rocking contact shoe carried by said extensible sections.

4. In a compressor a cylinder, a rotor eccentrically positioned therein, opposed radial [slots formed in the rotor, a vane in each slot,

a member connecting the same, a telescoping extensible section on the outer end of each vane, and a pair of extensible end sections on each vane carried by the aforesaid extensible section.

5. In a compressor, a cylinder, a rotor eccentrically positioned therein, opposed radial slots formed in the rotor, a vane in each slot, a member connecting the same, a telescoping extensible section on the outer end of each I however wish it understood that it ll 1 ii vane, a pair of extensible end sections on each vane, one at each end thereof, and a rocking contact shoe carried by the first named extensible section and the extensible end sections.

6. In a compressor, a cylinder, a rotor eccentrically positioned therein, opposed radial slots formed in the rotor, a vane in each slot, an adjustable member connecting the same, a telescoping face member on each vane, a spring interposed between each face section and each vane, and spring pressed end sections carried by the ends of the face member.

- 7. In a compressor a cylinder, a rotor eccentrically positioned therein, opposed radial slots formed in the rotor, a vane in each slot, an adjustable member connecting the same, a telescoping face member on each vane a spring interposed between each face section and each vane, the face member having recessed ends in line parallel with the ends of the base member, extensible sections car ried by the ends of the face member, springs mounted in the recesses of the ends of the face member for action against the extensible end sections, and a rocking contact shoe carried by each telescoping section.

8. In an engine of the character described a cylinder, a rotor eccentrically positioned therein, a pair of opposed radially positioned vanes slidably mounted in the rotor, a positive connectin member between the vanes, means permitt1ng manual adjustment there of to shorten or lengthen the vanes, and other means permitting automatic lengthening or shortening of the vanes during rotation of the rotor.

9. In an engine of the character described a cylinder, a rotor eccentrically positioned therein, a pair of opposed radially positioned vanes slidably mounted in the rotor, a positive connecting member between the vanes, means permitting manual adjustment thereof to shorten or engthen the vanes, an auxiliary vane section on each vane. and spring means interposed between the main vane sections and the auxiliary sections.

10. In a compressor of the character described a vane comprisin a base section, a telescoping extensible face section having end portions lying adjacent the ends of the base section, and a pair of extensible telescoping end sections supported by the ends of the face section, one being disposed at each end thereof.

11. In a compressor of the character described a vane comprising a base section, a telescoping face section having ends lying parallel with the ends of the base section, a spring interposed between said sections, a telescoping end section on each end of the face section, and springs interposed between said end sections and the face section.

12. In a compressor of the character described a vane comprising a base section, a telescoping face section, a spring interposed between said sections, a telescoping end section on each end of the face section, springs interposed between said end sections and the face section, and a rocking shoe carried by the face section and the end section.

13. In a compressor a cylinder, a rotor eccentrically positioned therein, radially disposed vanes carried bv the rotor and engaging the inner face of the cylinder, a pocket formed in the cylinder and a sealing shoe pivotally mounted in said pocket and engageable with the rotor.

In a compressor a cylinder, a rotor eccentrically positioned therein, radially disposed vanes carried by the rotor and engaging the inner face of the cylinder, a pocket formed in the cylinder, a sealing shoe pivotally mounted in said pocket and engageable with the rotor, and a spring interposed between one wall of the pocket and the shoe.

15. In a compressor a cylinder, a rotor eccentrically positioned therein, radially disposed vanes carried by the rotor and engaging the inner face of the cylinder, a pocket formed in the cylinder, a sealing shoe pivotally mounted in said pocket and engageable with the rotor, and means for exerting pneumatic pressure on the free end of the shoe.

16. In an engine of the character described a compressing cylinder, a rotor eccentrically positioned therein, a contact sealing shoe in the cylinder engageable with the rotor, a pivotal mounting for one end of the shoe, leaving the other end free, spring means exerting a constant pressure on the shoe, and means for exerting pneumatic pressure on the shoe during maximum compression.

17. In an engine of the character described, a compressing cylinder, a rotor eccentrically positioned therein, a contact sealing shoe in the cylinder engageable with the rotor, a pivotal mounting for one end of the shoe, said mounting leaving the other end of the shoe free, spring means exerting a constant pressure on the shoe, and means for transferring a portion of each compressed charge to a point behind the shoe where it will exert pressure on the shoe during the maximum compression of each charge admitted to the rotor.

18. In an engine of the character described, a compressing cylinder, a rotor eccentrically positioned therein, a contact sealing shoe in the cylinder engageable with the rotor, a pivotal mounting for one end of the shoe, said mounting leaving the other end of the shoe free, spring means exerting a constant pressure on the shoe, and

means for transferring a portion of each compressed charge to a point behind the shoe where it will exert pressure on the shoe during the maximum compression of each charge admitted to the rotor, said means comprising a chamber formed on the rear side of the shoe and a passage formed in the cylinder communicating with the compression space in the cylinder and said chamber.

19. In a compressor of the character de scribed the combination with the rotor and a cylinder enclosing the same, of a pair of head members one on each end of the cylinder, a pair of vanes radially disposed in the rotor, and packing rings carried byeach end of the rotor and engaging the respective cylinder heads, said packing rings comprising two pair of-semi-cirrcular rings on each end of the rotor, said rings being eccentric with re.- lation to the rotor.

20. In a compressor of the character described a rotor, and packing means on each end of the rotor, said means comprising two pai of semi-circular rings eccentrica1ly positioned with relation to each other, and grooves formed in the rotor for the reception of said rings. I

21. In a compressor of the character described a rotor, a pair of vanes carried thereby, a cylinder surrounding the rotor, a pair of cylinder heads on the cylinder enclosing the ends thereof, a contact shoe on the outer end of each vane, and a removable cover member on one of the heads with which the contact shoes are adapted to align and through which they may be removed.

22. In a compressor of the character described the combination with a cylinder, the heads and the rotor mounted within the cylinder, of a contact sealing shoe engaging the rotor, and a removable cover member on one of the heads, said cover member when removed permitting removal of the shoe.

23. In an engine of the character described, a cylinder, a rotor therein, radially disposed vanes slidably mounted in the rotor, a packing bar semi-circular in cross section extending across the outer face of each vane and contacting with the inner surface of the cylinder, a cylinder head on each end of the cylinder, an opening formed in one of the cylinder heads with which the semicircular packing bars are adapted to register and through which they may be inserted or removed, and a closure forsaid opening.

24. In an engine of the character described a cylinder, a rotor therein, a contact sealing shoe in the cylinder and engageable with the rotor, a cylinder head on each end of the cylinder, an opening formed in one of the cylinder heads in alignment with the contact sealing shoe, said opening having a shape conforming substantially to the shape of the sealing shoe, and being sufiieiently large to permit insertion or removal of the shoe, and a cover plate for said opening.

25. In an engine of the character described a cylinder, a rotor in the cylinder, said rotor having a central annular passage formed therein, a pair of head members one for each side of the cylinder, a bearing member in each head, a shaft extending through the cylinder, the rotor and the bearing members in the heads supporting the rotor, an annular passage formed in each head member exterior of the bearing members and communicating with the central passage in the rotor to permit air circulation and cooling, and means for circulating water around the cylinder and through the heads. HENRY A. CAMPBELL. 

